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arXiv · 1012.3080

Suzaku observation of the LINER NGC 4102

O. Gonzalez-Martin·I. Papadakis·V. Braito·J. Masegosa·I. Marquez·S. Mateos·J. A. Acosta-Pulido·M. A. Martinez·J. Ebrero·P. Esquej·P. O'Brien·J. Tueller·R. S. Warwick·M. G. Watson
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Abstract

Low ionisation nuclear emission-line region (LINER) nuclei have been claimed to be different than other active galactic nuclei (AGN) due to the presence of complex absorbing structures along the line-of-sight and/or an inefficient mode of accretion onto the supermassive black hole. However, this issue is still open. We have investigated the broad band X-ray spectrum of NGC 4102, one of the most luminous LINERs in the Swift/BAT survey. We studied a 80 ksec Suzaku spectrum of NGC 4102, together with archival Chandra and Swift/BAT observations. We also studied the optical (3.5m/TWIN at Calar Alto observatory) and near-infrared (WHT/LIRIS at Observatorio Roque los Muchachos) spectra that were taken contemporaneous to the Suzaku data. There is strong evidence that NGC 4102 is a Compton-thick AGN, as suggested by the Swift/BAT detected intrinsic continuum and the presence of a strong narrow, neutral FeKa emission line. We have also detected ionised FeXXV emission lines in the Suzaku spectrum of the source. NGC 4102 shows a variable soft excess found at a significantly higher flux state by the time of Suzaku observations when compared to Chandra observations. Finally, a complex structure of absorbers is seen with at least two absorbers apart from the Compton-thick one, derived from the X-ray spectral analysis and the optical extinction.

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O. Gonzalez-Martin, I. Papadakis, V. Braito, J. Masegosa, I. Marquez, S. Mateos, J. A. Acosta-Pulido, M. A. Martinez, J. Ebrero, P. Esquej, P. O'Brien, J. Tueller, R. S. Warwick, M. G. Watson. 2010-12-14. Suzaku observation of the LINER NGC 4102. https://doi.org/10.1051/0004-6361/201016097

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